The big Boeing jetliner looked a bit odd to aircraft buff Fred Hayes as it neared the runway at San Francisco International Airport on Saturday. It seemed to be low, and its nose was tilted sharply upward.

Then a banging sound echoed across the water, and the jet flipped nose-down and skidded in an orange-and-gray cloud. Hayes captured the scene on video while on a walk with his wife along San Francisco Bay, about a mile away.

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The crash-landing left two dead and hurt 182 people, six of whom were in critical condition Sunday. But 123 others walked away unhurt.

Hayes and his family were on a weekend visit to San Francisco, where he had a job interview on Friday. He said he had been focusing on a taxiing United Airlines jet when the Asiana flight caught his eye.

"When I caught the plane coming into view, everything looked fine at first until I kind of fixed my gaze on him, and I seen his nose up in the air," Hayes said. "And then I just totally locked on him. I thought he was going to take off and go up, and then he just kept going down."

The Boeing 777 appeared "maybe a little lower than some of the other planes" as it approached, "but I couldn't say that for sure," he told CNN's Don Lemon.

"My initial thought was that with the nose pitched up in the degree that it was that the pilot was maybe trying to divert the landing," said Hayes, who has no background in aviation. "As you can see in the video, it was pretty low at that point and that may or may not have been the case."

Investigators from the National Transportation Safety Board told a similar story Sunday afternoon. Asiana 214 appeared to be too low and too slow as it neared the runway, and the cockpit voice recorder indicates the crew tried to abort the landing less than two seconds before the crash, NTSB Chairman Deborah Hersman told reporters.

Aviation expert Jim Tilmon called the video "remarkable footage" that will likely be analyzed by investigators "over and over again."

Once the jet hit the ground, it skidded nose-down and sideways, spinning counterclockwise and catching fire. Tilmon, a former jetliner pilot himself, told CNN the pilot showed "a fair amount of skill" in keeping the jet from flipping over.

"If that had happened -- my goodness, this would be a completely different kind of report to make today," he said. "Because there would sure have been a great deal more injuries as a result."

Hayes said a "thunder-like" sound rang across the bay when the more than 200-foot-long jetliner slammed into the ground.

"Every time a section hit, you could hear that boom and that sound," he said. After three or four "really big booms," he said, "It just kind of slid and came to a stop."

He and his wife watched as the emergency slides deployed and passengers began to slide down them away from the wrecked jet. He said he hoped crash investigators could learn from the video he shot.

"The only thing we can say is we're just really happy that a lot of people survived, because it wasn't looking good for them folks on that plane for sure," Hayes said.

Nearly three hours after the crash, David Eun walked through customs at San Francisco International Airport. By then, the adrenaline rush was subsiding enough that he could begin processing the enormity of it all.